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    <title>Document</title>
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    <!-- 分割数组的最多方案数 -->
    <script>
      var waysToPartition = function (nums, k) {
        let lMap = new Map()
        let rMap = new Map()
        let sum = 0
        for (let num of nums) {
          sum += num
        }
        let rDiff = sum
        let lDiff = -sum
        let max = 0
        for (let i = 0; i < nums.length; i++) {
          lDiff += 2 * nums[i]
          if (i == nums.length - 1) max = lMap.get(0) || 0
          lMap.set(lDiff, (lMap.get(lDiff) || 0) + 1)
        }
        rMap.set(rDiff, -1)
        for (let i = nums.length - 1; i >= 0; i--) {
          let tmp = k - nums[i]
          lMap.set(lDiff, (lMap.get(lDiff) || 0) - 1)
          rMap.set(rDiff, (rMap.get(rDiff) || 0) + 1)
          lDiff -= 2 * nums[i]
          rDiff -= 2 * nums[i]
          max = Math.max((rMap.get(-tmp) || 0) + (lMap.get(tmp) || 0), max)
        }
        return max
      }
      console.log(waysToPartition([2, -1, 2], 3))
    </script>
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